x+2/x=c+2/c~x1=c,x2=2/c;x+2/(x-1)=a+2/(a-1);(x-1)+2/(x-1)=(a-1)+2/(a-1);x1-1=a-1;x2-1=2/(a-1);x1=a;x2=1+2/(a-1)
yun~
=1000
等于 头疼
